Manufacture of magnesium salts of high molecular weight alkylated hydroxy aromatic copounds and their use in lubricating oils



sept 16, 1952 J. W. HUTCHESON 2,510,982

l MANUFACTURE oF MAGNESIUM sims oF HIGH MOLECULAR WEIGHT ALKYLATED- HYDROXY AROMATC COMPOUNDS AND THEIR USE 1N LUBRICATING ons Filed Feb. 11, 195o INVEN TOR.

:fo/f W /v/a Tc//so/v 'BY A Patented Sept. 16, 1952 MANUFACTURE OF MAGNESIUM SALTS OF HIGH MOLECULAR WEIGHT ALKYLATED HYDROXY AROMATIC COMPOUNDS AND THEIR USE IN LUBRICATING OILS John W. Hutcheson, Beacon, N. Y., assignor to The Texas Company, New York, N. Y., a corporation of Delaware Application February 11, 1950, Serial No. 143,761

5 Claims. l

This invention relates to the manufacture of magnesium salts f high molecular weight alkylated hydroxy aromatic compounds, such as alkyl phenols, wherein the substituent alkyl group on each benzene nucleus contains from l to 30 carbon atoms.

The magnesium salts of alkylated hydroxy aromatic compounds, such as alkyl phenols, having one or more high molecular weight alkyl side chains substituted on the ring, are valuable additives for mineral lubricating oil. The magnesium alkyl phenolate of the present invention is particularly useful, when used in conjunction with a zinc alkyl phenolate, as an additive for an airplane engine oil of the highly refined residual type, as disclosed and claimed in the copending application of Frederic C. McCoy, Bill L. Benge, Edwin C. Knowles and Charles C. Towne, Serial Number 143,836, filed of even date herewith.

Polyvalent metal salts of lower molecular weight alkyl phenols or other alkylated hydroxy aromatic hydrocarbons, have generally been prepared by a double decomposition procedure, involving first forming the alkali metal salt of the alkyl phenol, followed by reaction with a soluble polyvalent metal salt. It has been found that this procedure is unsatisfactory in the preparation of the magnesium salts of the present invention, since serious filtration difliculties are encountered, and the quality of the final product is l' unsatisfactory with respect to solubility and effectiveness as a residual mineral lubricating oil additive.

It has also been proposed to form the polyvalent metal salts of such alkyl phenols by the direct alcoholate procedure, wherein the polyvalent metal alcoholate, such as a methylate or ethylate, is reacted directly with the alkyl phenol. It has been found that this procedure is also unsatisfactory for the synthesis of magnesium salts of the desired solubility and quality for residual lubricating oil additives, when using the high molecular weight C-C30 alkyl phenols, unless certain special and critical processing conditions are employed.

It is accordingly a principal object of the present invention to provide an improved process of synthesizing the magnesium salts of high molecular weight alkylated hydroxy aromatic hydrocarbons, such as alkyl phenols, wherein the substituent alkyl group of the benzene nucleus contains from 15 to 30 carbon atoms, in order to provide products of the required solubility and quality to serve as lubricating oil additives, particularly of the residual lubricating oil type.

Other objects and advantages of the present invention will be apparent from the following description taken in conjunction with the attached drawing and appended claims.

The drawing is a flow sheet of the method of synthesis of a preferred magnesium alkyl phenolate in accordance with the present invention.

Any suitable alkylated hydroxy aromatic hydrocarbon, wherein the substituent alkyl group on the benzene nucleus contains from l5 to 30 carbon atoms, is a satisfactory starting material for purposes of the present invention. The preferred material from the standpoint of additive manufacture is an alkyl phenol prepared by alkylating a mononuclear monohydroxy aromatic hydrocarbon, such as phenol, cresol or other alkyl phenol. with an olefin polymer, such as a propylene polymer, containing from about 16 to 30 carbon atoms. Also, hydrogenated cardanol producing a C15 alkyl phenol is a satisfactory starting material. Likewise, alkylated mononuclear polyhydroxy aromatic hydrocarbons, such as hydroquinone, pyrogallol and other dihydric and trihydric phenols, can be employed. Also, alkylated polynuclear hydroxy aromatic hydrocarbons, such as the naphthols, can be used. From the standpoints of availability and economy, alkyl phenol prepared by alkylating phenol with a Cia-Cin,

and preferably C18-C26, propylene polymer in the i presence of anhydrous HF catalyst as disclosed and claimed in the copending application of Louis B. Bos, Serial No. 143,784, filed of even date herewith, or in the presence of AlClTHSO:l complex catalyst as disclosed and claimed in the cepending application of Fred W. Moore and Herman D. Kluge, Serial No. 143,782, filed of even date herewith, is preferred. For the purpose of ease in description, a C15-C30 alkyl phenol of the foregoing type will be referred to in the following text; but it is to be understood that this is solely by way of example, and that the description applies to the other alkylated hydroxy aromatic hydrocarbons specified.

The synthesis of the magnesium salt of the C15-Cao alkyl phenol in accordance with the present invention involves an improvement on the previously suggested direct alcoholate procedure, wherein the magnesium alcoholate of a Ci-Cs anhydrous aliphatic alcohol is reacted directiy with the alkyl phenol. Preferably magnesium methylate, prepared by reacting magnesium turnings with an excess of anhydrous methyl alcohol, is employed. However, the same procedure applies to the other magnesium alcoholates of the Cz-Cs anhydrous aliphatic alcohols. The reaction between the alkyl phenol and magnesium methylate to produce the magnesium salt is repre sented by the following equation:

-OMgO- ZCHQOH in accordance with the present invention, the reaction is carried out under substantially anhydrous conditions, employing somewhat less than the stoichiometric equivalent amount of magnesiurn methylate or other alcoholate in solution in an excess of the corresponding anhydrous alcoplace under mildly elevated temperature conditions at which the alcohol is distilled on, leaving an organic solvent solution of the magnesium alkyl phenolate which is then nltered while hot. A mineral lubricating oil is then added to t ho filtrate, the organic solvent is stripped off l; the aid of a dry gas to maintain the anhydrous conditions, thereby leaving a mineral lubricating oil concentrate of the magnesium alkyl phenolate. Finally, this mineral oil concentrate is subjected to a controlled heat treatment at about 100- 180 C. for at least 3 hours, and up to about l2 hours, preferably with stirring at about 125 C, for 4-8 hours. the concentrate from solidifying to a gel upon cooling, and also to improve the solubility of the magnesium salt in a residual mineral lubricating oil. This heat treatment is an important step in obtaining a magnesium alkyl-phenolate additive ie of the desired quality for a residual lubricating oil, such as an airplane engine oil,

Referring to the drawing, the C15-C30 alkyl phenol is mixed with about an equal volume of a suitable organic solvent, such as toluene, Xylene.

or any other organic liquid which is a solvent for both the alkyl phenol and magnesium salt and which boils above the boiling point of water as well as the aliphatic alcohol employed in the process, and yet can be readily stripped from the reaction product at a later stage. As shown, toluene is generally preferred for this purpose. The alkyl phenol solution in toluene is charged to stirred reactor fitted with a condenser having water trap; stantially anhydrous by drying at a toluene reuxing temperature, with any separated water collecting in the water trap being removed.

The magnesium alcoholate of a (J1-C5 anhydrous aliphatic alcohol ls prepared in a separate 7'5 reactor equipped with a condenser. ,es shown, absolute methyl alcohol is preferred for this purpose. Magnesium turnings are added to the absolute methyl alcohol in the proportion of about one atomic quantity of magnesium per liter of This has been found to prevent and the reactants are rendered subalcohol; and the latter is heated to refluxing conditions. The clear solution of the resulting' niagnesium rnethylate dissolved in excess methyl alcohol is then added dropwise at about llil-5f C to the iirst mentioned stirred reactor until slightly less than the stoichiometric equivalent amount of magnesium methylate (1/2 mol per l mol of the alkyl phenol) has been added. Anhydrous conditions are maintained in this reaction :1nd throughout the balance of the process.

Following the addition of the magnesium meth-- ylate solution, the temperature is then increased, and the methyl alcohol distilled over and removed by the trap. The resulting toluene solution of magnesium alkyl phenolate is then filtered while hot. Suicient mineral lubricating oil, such as a rened parafn base distillate motor oil of about SAE 10 grade, or a refined naphthene base oil having an SUS viscosity at 100 F. of about 300, is added to produ-ce an ultimate concentrate of the magnesium alkyl phenolate in the lubricat ing oil of about lll-50%, preferablylaoout 25%. The toluene solvent is then stripped from the lubricating oil concentrate distillation with the aid of a dry gas, such as dry air. The resulting concentrate is then subjected to the controlled heat treatment with stirring at a temperature of about 1GO-189 C. for in excess of 3 hours and up to about l2 hours, in order to prevent gel formation and maintain the lubricating oil concentrate completely uid when cooled to room temperature, and also to improve the solubility of the magnesium alkyl phenolate in a residual minerai lubricating oil, such as an airplane engine oil.

The following examples are given to further illustrate the present invention:

EXALPLE l 206 grams of alkyl phenol (lf2 mol), wherein the substituent alkyl group on the benzene nucleus contained an average of 23 carbon atoms, were dissolved in 809 mls. of toluene, and 212 grams of a naphthene base distillate lubricating oil having an SUS viscosity at 100 F. of 315. The resulting mix was refiuXed until apparently diy. l5 grams of magnesium turnings were reacted in a separate vessel with 500 mls of absolute methyl alcohol. A sample of the resultant niagnesiuzn methyiate solution was withdrawn and titrated with standard HC1, from which the quantity of the magnesium methylate solution was calculated in order to give slightly less than the stoichiometric equivalent amount of magnesium for complete neutralization of the quantity of alkyl phenol present. The stoichiometric equivalent amount reouired di grams 1/4'mol) of inagnesiuzn; and suiiicient magnesium methylate solution was added dropwisc at 52 C. to the reactor containing the toluene-lubricating oil Solution or the alkyl phenol to provide approximately 6.0 grams of magnesium. Ordinarily, only a slight deficiency of the magnesium 'methylate solution is satisfactory, such as about (ll-1.6% calculated as magnesium. The reactants -were heated to distill oilr the methyl alcohol, and the hot solution iiltered. The toluene was then stripped, and the lubricating oil concentrate allowed to cool to room temperature without the previously described heat treatment. The product solidiied to a gel. which analyzed to an ash content of 2.42, check 2.35%, the theoretical ash content being 2.35%. The gel was diiicultly soluble in a paraflin base distillate lubricating oil of an SAE l0 grade such that less than 1% by weight .of the magnesium alkyl phenolate could be maintained in solution therein on storage.

In a previous preparation utilizing the same procedure, except that a slight excess (1A, mol 0.9 gram) of the magnesium methylate solution had been added to the alkyl phenol, the resulting gel which formed on cooling of the final lubricating oil concentrate of the magnesium alkyl phenolate analyzed to an ash content of 2.78%, as compared to a theoretical ash content of 2.35%. This gel with high ash content Was substantially insoluble in the distillate paraffin base lubricating oil of SAE grade.

EXAMPLE 2 The gel product from Example 1 (first described procedure) was dissolved in 342 grams of benzene, and an additional 342 grams of the naphthene base distillate lubricating oil sufficient to make an ultimate 25% concentrate were added. The benzene was then stripped, and a yield of 680 grams of resulting concentrate was obtained which remained fluid when cooled to room temperature. The product analyzed to an ash content of 1.22%, with a theoretical ash content of 1.18%, and was readily soluble in the SAE 10 paran base lubricating oil to the extent of 1% of the magnesium alkyl phenolate. Apparently the additional heating altered the character of the product to improve its fluidity and solubility. This product was engine tested, but the results were inferior as set forth in greater detail hereinbelow. Apparently the prior addition of the lubricating oil before the completion of the reaction interfered with the attainment of a product of desired quality, probably because of the difficulty of maintaining the reactants anhydrous in the presence of the lubricating oil.

EXAMPLE 3 642 grams of C24 alkyl phenol (l1/2 mois) were dissolved in 2 liters of toluene and refluxed until dry. 30 grams of magnesium turnings were reacted in 1000 mls. of absolute methyl alcohol. The magnesium content was calculated and slightly less than the stoichiometric equivalent amount of the magnesium methylate solution was added dropwise at 40-50 C. The temperature was increased and the methyl alcohol removed by the trap. The material Was filtered hot, and 1953 grams of the aforesaid naphthene base distillate lubricating oil were added and the solvent stripped. The heat treatment was not employed. 2530 grams of a lubricating oil concentrate of the magnesium alkyl phenolate were obtained which became quite viscous but remained fluid on cooling to room temperature. The product analyzed to an ash content of 1.19% with a theoretical ash content of 1.15% and was soluble to the extent of 1% of the pure magnesium alkyl phenolate in the SAE 10 paraffin base motor oil. The product was employed in engine testing, but the results were still not satisfactory as discussed more fully hereinbelow.

EXAMPLE 4 The same procedure was employed as in Example 3 above, using the following quantities of reactants:

C24 alkyl phenol 1260 grams (3 mois) Magnesium turnings- 50 grams Methyl alcohol absolute-. 2000 mls. Toluene 4 ,liters Distillate naphthene base lubricating oil 3879 grams A yield of 4643 grams of a lubricating oil concentrate of the magnesium alkyl phenolate was obtained which was very viscous when cooled to room temperature. While the product was soluble to the extent of 1% of the magnesium alkyl phenolate in the SAE 10 distillate lubricating oil, it was not soluble to the extent of 1% in a refined paraiiin base residual lubricating oil of the airplane engine oil type. This residual lubricating oil was rened by solvent deasphalting, solvent refining, solvent dewaxing, clay contacting and clay filtering. Airplane engine oils of this type generally have a SUS viscosity at 210 F. of about 80-130. The particular oil selected for this test had a SUS viscosity at 210 F. of about 120. This product was also engine tested, but the results were not satisfactory as discussed further hereinbelow.

EXANIPLE5 Approximately 3,000 grams of the viscous lubricating oil concentrate obtained in Example 4 above were placed in beakers in a steam chest at C. for 4-6 hours. Upon cooling, the product was fluid and soluble to the extent of 1% of the pure magnesium alkyl phenolate in the previously mentioned residual airplane engine oil. The product was engine tested with very satisfactory results as described hereinbelow.

EXAMPLE 6 Based on the foregoing results including the engine testing, the following is given as an example of the Standard procedure developed in synthesizing the magnesium alkyl phenolate of the desired solubility and quality, in accordance with the present invention. 416 grams of C23 alkyl phenol were dissolved in 2 liters of toluene, and the reactants reuxed until dry. 25 grams of magnesium turnings were reacted in 1,000 mls. of absolute methyl alcohol. The magnesium content Was calculated, and slightly less than the theoretical amount of the magnesium methylate solution added dropwise at 4050 C., followed by distilling off the methyl alcohol. The toluene solution was filtered, and 1280 grams of the naphthene base distillate lubricating oil added. The solvent was then stripped with the aid of dry air. The resulting lubricating oil concentrate was then heat treated at 125 C. for 4-6 hours. 1647 grams of a 25% concentrate of the magnesium alkyl phenolate were obtained, which had substantially theoretical ash content, possessed good solubility properties, and gave excellent engine test results as hereinafter described.

As set forth more fully in the above mentioned copending application of Frederic C. McCoy, Bill L. Benge, Edwin C. Knowles and Charles C. Towne, the magnesium alkyl phenolate produced in accordance With the present invention is ernployed in conjunction with a second metal alkyl phenolate, namely zinc alkyl phenolate, in an airplane engine oil, to maintain engine cleanliness in high temperature heavy duty service, and also to prevent the formation of objectionable combustion chamber deposits. Final proof of the quality of the magnesium alkyl phenolate preparation was therefore secured by the actual engine testing of the preparation in conjunction With a second metal alkyl phenolate in an airplane engine oil, as set forth in the following Table I. In that table, MP designates the magnesium alkyl phenolate, ZP the corresponding zinc salt and TP the corresponding tin salt. The numeral following the designation for the metallic phenolate 7 signifies the average carbon atom content of the alkyl side chain on each benzene nucleus of the salt The CFR high speed engine test of the table is the quality of the magnesium phenolate products.

Run l of the table employed a magnesium C23 alkyl phenolate produced by a double decoma reliable screening test for determining the position reaction, wherein sodium amylate was ability of a crank case lubricating oil to reduce first reacted with the alkyl 131161101, and then the engine deposits under severe operating condiresulting sodium alkyl phenolate reacted with tions. This test is carried out with a standard magnesium chloride. Other attempts to prepare CFR, single cylinder engine operating under the the magnesium salt by this double decomposition following conditions: i0 reaction, including the use of sodium butylate and also magnesium acetate in the reaction, had Compression ratio 6-51 resulted in failure due to nltration difficulties. SP 1R-PM 1800 This sodium amylate procedure resulted in a A11'/ fuel ratio 1.321A magnesium alkyl phenolate of fairly satisfactory JhckettemFJature---u 285 F- 15 ash content and solubility sov that it could be Oil in temperature' 185 F. employed for engine testing; but the engine test OOut temperature-v 200,F- showed ,the product to be of unsatisfactory F1181 100 9ct/ah@ (hllhlmum) quality as a detergent additive for crank case aVlaFOn type con' lubricating oil, since it failed to maintain the I taining4 cc. TEL/gal. 20 desired engine cleanliness. Duratloh of mh 50 hours Run 2 of the table sets forth the results secured In this test, electrical measurements are taken m the engine testing of the magnesium C23 alkyl of the piston skirt deposit with respect to the exphenolate produced by thmethylae procedmfe tent or percentage of Surface area of the piston of Example 2 above, wherein the mineral lubriskirt which is Covered by the lacquer deposit 25 cating oil yvas added prior to the reaction. Even at the termination of each run, together with the though thlS DlGdllCil WS Prepared byl using average thickness of the deposit expressed in slightly less than the stoichiometric equivalent inches X 10-4 Good reproducibility from run amount of magnesium methylate solution, and to run is obtained in the piston skirt lacquer dewas m effect heat mme@ by the Second add" posit; and the test is therefore recognized as tion of solvent and lubricating oil to the gel an accurate Aindication of the engine cleanliness of Produc-'3 0f Example l, nevertheless this Prepara* the oii composition under tesi. tion also failed to exhibit the desired engine The following results were obtained in this eahhhess properties CFR high speed engine test, utilizing the mag- Run 3 oi the table empioyed the magnesium nesium alkyl phenolate preparations as described C24 alkyl phenolate lDlOdllCt produced by EX- herein in conjunction with either tin phenolate ample 3, inl/Owing the S13-Called Standard or zinc phenolate in the proportions indicated methylate procedure except omitting the final in a residual airplane engine oil having an SUS heat treating Step- Run 4 likewise employed a viscosity at 210 F. of about 120 and designated product made by this same procedure. Run 5 AEO 120.v 40 employed the product of Example 4 above. In

TabZeI i CFR High speed Pistift @it iigixiiwirhemiaie Procedure Poegft Sfodnifilg Pogfcft L Covered, Thickness Percent in. l0*

i. Na Amyiate-Mr-23 0.5 T12-24 1.0 i2 0,19 2. Mg Methylate MP-23 (prior addition o! iube nii) i 0 FP-2i 1.0 is 0.02 3. Mg Methylate LMP-24 (without heat treatment) 1. 0 'FP-24 0. .i l5 0. l2 4. Mg Methylate MP-24 (without heat treatment) l. 0 ZP-24 O. 5 l2 O. 03 5. Mg Methylate MP-24 (without heat treatment) l. 0 ZP23 O. 5 18 O. 08 6. Mg Methylate-Product of Run 5 with heat treatment 1.0 ZP-24 0. 5 0 0. 00 7. Standard-MP-23 1.0 Z13-23 0.5 o 0.00 s. sraiidaraMP-2o n 1.0 zie-20 0.5 0 0.00 9. standard-Mem i 0 zPii 0.5 0 om l0. Base Oil Alone AEO 120 80 2. U

Run 10 of the foregoing table shows that the each case, the product is seen to be of inferior base oil alone fails to maintain engine cleanliquality with respect to maintaining the desired ness, since the piston was 80% covered with a engine cleanliness. comparatively thick lacquer deposit. On the Run 6 employed the heat treated product of other hand, a magnesium alkyl phenolate of the Example 5, and the engine test showed this prodproper quality in conjunction with either a zinc uct to be of good quality as evidenced by the lack alkyl phenolate or a tin alkyl phenolate. of the of measurable piston skirt deposit. Run 7 emproper quality, when employed in proportion ployed the product of Example 6; and Runs 8 ranges of the order shown in the table, will andQemployed other preparations of magnesium maintain good engine cleanliness, and give in .this alkyl phenolate produced by the so-called standengine test a piston substantially Without measard procedure of Example 6. In each case, the urable lacquer deposit on the skirt. The zinc product was of the desired high quality as shown and tin phenolate additives employed in the runs by the satisfactory engine test. of this table were known to be of good quality; The characteristics of the magnesium alkyl so the test results are an accurate indication of phenolates employed in Runs 2-9 inclusive of Table I, with respect to ash and magnesium conscope thereof, and, therefore. -only such limitent, and storage data on solubility, are set forth tations should be imposed as are indicated in the in the following Table II: appended claims.

Table II Ash Ash Mg Mg Mg Alglkyl Psrate Weight Percent Weight Percent Storage Data repara m Percent Theory Percent Theory Run 2 of Table l.. 1. 22 1.18 1% soluble in SAE 10 oil. RunofTable I 1.19 1.15 Do. Run 4 of Table I.- 1. is 1.12 o. 72 o. es Do. n Run 5 of Table I 1.25 l. 12 0. 76 0. 68 1% soluble in SAE l0 oil but l not completely soluble in Ano 12o. Rlmof TableI i 1% ln AEO 120 clear after 3 months. Run 7 of 'rooie I- 1. 23l 1 is o. 72 o. 7i Do. Run 8 of Table I 1.32 1 28 (l. 79 0.78 Do. Run 9 of 'rabia 1 1. 2s 1.24 o. 76 0.15 Do.

In each case, the ash and magnesium contents I claim:

of the products analyzed close to theoretical. l. In the manufacture of a magnesium salt of This is to be compared with the product of Exan alkyl substituted hydroxy aromatic hydroa-mple l above using an equivalent or excess carbon consisting of carbon, hydrogen and oxyamount of magnesium methylate. In the latter gen, wherein the alkyl substituent on the ring case, the ash content is quite high; and products contains from l5 to 30 carbon atoms, the method made by this procedure were uniformly unsatiswhich comprises reacting under substantially anfaotory with respect to solubility and selling hydrous conditions the alkyl substitutes hydroxy properties. It is postulated that, Where the alkyl aromatic hydrocarbon consisting of carbon, h5

phenol is not present in the reacting mX irl EX- drogen and oxygen in solution in an organic sole Cess of the stolchometrlc equivalent amount of vent with a magnesium alcoholate solution conmaenesum methylate, Some complex other than sisting of magnesium alcoholate dissolved in an the desired magnesium alkyl phenolate. such as excess of the corresponding anhydrous alcohol a CompleX COIltaning 50H19 methylate groups atselected from the group consisting of the lower tached t0 50m@ magnesium mOnOPheIlOlae, fGlmS molecular weight aliphatic alcohols containing the reaction. The presence of such Complex from 1 to 5 carbon atoms in the molecule, sai-:i in the product would of course increase the ash organic Sohlen@ having a higher boiling point content above the theoretical for magnesium than that of Water as Wou as said alcohol, heatalkyl phenlate. and apparently C-Oltfbutes t0 ing said reaction mix at mildly elevated tempera-- the insolubility and other undesirable properties hires at which the aiiphotio eioohoi is distiiioo 0f the resulting DlOdllCt. off but below the boiling point of said organic While the ash and magnesium Contents 0f the 40 solvent, to obtain a solution of the magnesium Products 0f Runs 3 5 inclusive 0f Table are salt of the alkyl substituted hydroxy aromatic fairly close to theoretical, it is noted from Table hydrooaroou ln the Said organic suivent, the II that the Solubility 0f these products which Wee quantity of magnesium alcoholate being less than not heat treated is not satisfactory in the residual the calculated Stoohometrlo amount required type of mineras lubricating Ong The products for neutralization of the quantity of alkyl subprepared by this procedure omitting the heat situted hydroxy aromatic hydrocarbon present.

treating step were mainly gels of unsatisfactory 2' The method alooordlng to Claim 1y wherein solubility in the residual lubricating oil so that the alkyl substltuted hydroxy aromas-o hydro they could not even be employed for engine test- Carbon ls a cls cz 2Llkyl phenol ing' And the few products of this chal-actes 5U 3. The method according to claim l, wherein which could be employed for engine testing um' the organic solvent solution is filtered, mineral formly gave inferior results with respect to en' lubricating oil is added, and the organic solvent gine cleanliness. 'It is postulated that some poly- Temoved by Strluplug Wlth dry gas to rooovo a merzatlon reactlon tends to take place in the concentrate of the magnesium alkyl substituted reaction forming product which is responsible hydroxy Tomado hydrocarbon ln the mineral for the gel formation or substantial viscosity inlubricating oil crease, as Well as the poor solubility and engine 1 En the 'manufacture of a magnesium solo detergent characteristics.; and that the heat of a C15C3o alkyl substituted hydroxy aromatic treatment breaks down this polymer and converts hydrocarbon conslstlng of Carbon, hydrogen and the reaction product to the desired magnesium 6o Ovygeu tug method Wluch comprlsos reaoune a salt. u l c' C15-Cro allryl substituted hydroxy aromatic hy on the other hang theproducts made by the drocarbon consisting of carbon, hydrogen and stlngad procedure lllnclumg the hiaat treattmet oxygen in solution in an organic solvent of higher a a e proper as an magnesum con en s, .A n n and have excellent solubility in the residual oil olglggtcaqegtlly 155012213;

as evidenced by the fact that lf? of the ma neslum alkyl phenolate n the arplane engle nesium methylate dissolved in anhydrous methyl oil of grade 120 remained as a clear solution after alcohol at a mildly elevated temperature at which Storage of thro@ months. The Syuthesls puh the methyl alcohol is distilled olf but below the cedure of the present invention has been found boiling Poms 0f said Organic solvent' thereby to uniformly give Satisfactory products of lugo leaving the magnesium salt of the C15-Coo alkyl quality Without difculty. hydroxy aromatic hydrocarbon in solution in the Obviously many modifications and variationg organic solvent, ltering the last mentioned soluof the invention, as hereinbefore set forth, may tion. adding mineral lubricating oil. removing be made Without departing from the spirit and the solvent to obtain a mineral oil concentrate of the said magnesium salt, and `heat treating the said concentrate at a temperature of about 100- 180" C. for a period of at least 3 hours until the concentrate remains fluid upon cooling to room temperature and becomes soluble in a refined residual mineral lubricating oil to the extent of dissolving at least 1% by weight of the magnesium salt therein.

5. The method in the manufacture of magnesium Cia-C26 alkyl phenol, which comprises reacting under substantially anhydrous conditions a Cia-C25 alkyl phenol in solution in toluene with slightly less than the stoichiometric equivalent amount of magnesium methylate in solution in anhydrous methyl alcohol at a mildly elevated temperature above the boiling point of methyl alcohol to distill off the alcohol. but below the boiling point of toluene to obtain a toluene solution of the magnesium Cia-C25 alkyl phenol, fdltering the last mentioned solution while hot,

12 adding a distillate mineral lubricating oil, removing the toluene by stripping with the aid of dry air to obtain a lubricating oil concentrate of the said magnesium salt, and heat treating the said concentrate With stirring at a temperature of about 1GO-180 C. for about 4-8 hours to prevent gel formation of the concentrate upon cooling and to improve the solubility of the magnesium salt in a residual mineral lubricating oil.

JOHN W. HUTCHESON.

REFERENCES CITED The following references are of record in the le of this patent:

UNlTED STATES PATENTS Number Name Date 2,362,289 Mikeska Nov. 7, 1944 2,362,292 McNab Nov. 7, 1944 McNab et al. May 7, 1946 

1. IN THE MANUFACTURE OF A MAGNESIUM SALT OF AN ALKYL SUBSTITUTED HYDROXY AROMATIC HYDROCARBON CONSISTING OF CARBON, HYDROGEN AND OXYGEN, WHEREIN THE ALKYL SUBSTITUENTS ON THE RING CONTAINES FROM 15 TO 30 CARBON ATOMS, THE METHOD WHICH COMPRISES REACTING UNDER SUBSTANTIALLY ANHYDROUS CONDITIONS THE ALKYL SUBSTITUTED HYDROXY AROMATIC HYDROCARBON CONSISTING OF CARBON, HYDROGEN AND OXYGEN IN SOLUTION IN AN ORGANIC SOLVENT WITH A MAGNESIUM ALCOHOLATE SOLUTION CONSISTING OF MAGNESIUM ALCOHOLATE DISSOLVED IN AN EXCESS OF THE CORRESPONDING ANHYDROUS ALCOHOL SELECTED FROM THE GROUP CONSISTING OF THE LOWER MOLECULAR WEIGHT ALIPHATIC ALCOHOLS CONTAINING FROM 1 TO 5 CARBON ATOMS IN THE MOLECULE, SAID ORGANIC SOLVENT HAVING A HIGHER BOILING POINT THAN THAT OF WATER AS WELL AS SAID ALCOHOL, HEATING SAID REACTION MIX AT MILDLY ELEVATED TEMPERATURES AT WHICH THE ALIPHATIC ALCOHOL IS DISTILLED OFF BUT BELOW THE BOILING POINT OF SAID ORGANIC SOLVENT, TO OBTAIN A SOLUTION OF THE MAGNESIUM SALT OF THE ALKYL SUBSTITUTED HYDROXY AROMATIC HYDROCARBON IN THE SAID ORGANIC SOLVENT, THE QUANTITY OF MAGNESIUM ALCOHOLATE BEING LESS THAN THE CALCULATED STOICHIOMETRIC AMOUNT REQUIRED FOR NEUTRALIZATION OF THE QUANTITY OF ALKYL SUBSITUTED HYDROXY AROMATIC HYDROCARBON PRESENT.
 3. THE METHOD ACCORDING TO CLAIM 1, WHEREIN THE ORGANIC SOLVENT SOLUTION IS FILTERED, MINERAL LUBRICATING OIL IS ADDED, AND THE ORGANIC SOLVENT REMOVED BY STRIPPING WITH DRY GAS TO RECOVER A CONCENTRATE OF THE MAGNESIUM ALKYL SUBSTITUTED HYDROXY AROMATIC HYDROCARBON IN THE MINERAL LUBRICATING OIL. 